ubuntu-18.04 安裝 zookeeper-3.4.13

本文記錄了我安裝zookeeper的方法，最後運行了一個單機的實例驗證安裝。

一、安裝JDK

因爲zookeeper採用Java編寫的，因此咱們須要Java環境才能運行 此處咱們採用open-jdk-8 直接一行命令便可安裝

$ sudo apt-get install openjdk-8-jre
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二、下載zookeeper

打開zookeeper官網，能夠找到對應的下載地址: archive.apache.org/dist/zookee…

使用wget下載：

$ wget https://archive.apache.org/dist/zookeeper/zookeeper-3.4.13/zookeeper-3.4.13.tar.gz
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三、解壓zookeeper

下載下來的文件是壓縮文件，所以，咱們須要解壓

$ tar -xvf zookeeper-3.4.13.tar.gz
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四、移動解壓的文件夾到安裝目錄

安裝目錄能夠爲任意，此處咱們安裝在/usr/local/zookeeper/下，所以，將剛纔下載解壓完成的文件夾移動到/usr/local/zookeeper/

$ mv zookeeper-3.4.13 /usr/local/zookeeper/zookeeper-3.4.13
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五、爲zookeeper建立軟連接

爲了方便之後zookeeper的版本更新，咱們安裝zookeeper的時候能夠在同級目錄下建立一個不帶版本號的軟連接，而後將其指向帶zookeeper的真正目錄

即建立一個名爲/usr/local/zookeeper/apache-zookeeper的軟連接，指向/usr/local/zookeeper/zookeeper-3.4.13，之後更新版本的話，只須要修改軟連接的指向，而咱們配置的環境變量都不須要作任何更改

$ ln -s /usr/local/zookeeper/zookeeper-3.4.13 /usr/local/zookeeper/apache-zookeeper
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四、修改PATH

將zookeeper添加到環境變量

$ vim /etc/profile
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新增下面兩行

# 此處使用剛剛建立的軟連接
export ZK_HOME=/usr/local/zookeeper/apache-zookeeper
export PATH=$ZK_HOME/bin:$PATH
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讓剛纔修改的path生效

$ source /etc/profile
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此時，zookeeper的安裝完成，啓動一個單機版的測試一下

五、修改zoo.cfg文件

zookeeper啓動時候，會讀取conf文件夾下的zoo.cfg做爲配置文件，所以，咱們能夠將源碼提供的示例配置文件複製一個，作一些修改

# 進入配置文件目錄
$ cd /usr/local/zookeeper/apache-zookeeper/conf

# 複製示例配置文件
cp zoo_sample.cfg zoo.cfg

# 修改 zoo.cfg 配置文件
vim zoo.cfg
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修改數據存放位置 dataDir=/usr/local/zookeeper/data

# The number of milliseconds of each tick
tickTime=2000
# The number of ticks that the initial
# synchronization phase can take
initLimit=10
# The number of ticks that can pass between
# sending a request and getting an acknowledgement
syncLimit=5
# the directory where the snapshot is stored.
# do not use /tmp for storage, /tmp here is just
# example sakes.


# 只須要修改此處爲zookeeper數據存放位置
dataDir=/usr/local/zookeeper/data
# the port at which the clients will connect
clientPort=2181
# the maximum number of client connections.
# increase this if you need to handle more clients
#maxClientCnxns=60
#
# Be sure to read the maintenance section of the
# administrator guide before turning on autopurge.
#
# http://zookeeper.apache.org/doc/current/zookeeperAdmin.html#sc_maintenance
#
# The number of snapshots to retain in dataDir
#autopurge.snapRetainCount=3
# Purge task interval in hours
# Set to "0" to disable auto purge feature
#autopurge.purgeInterval=1 
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六、開始運行

進入bin目錄，執行運行命令(因爲剛纔設置了zookeeper到環境變量PATH裏面，因此，咱們其實能夠在任何目錄下執行下面的命令)

# 進入bin目錄
$ cd /usr/local/zookeeper/apache-zookeeper/bin

# 執行啓動命令
$ ./zkServer.sh start

ZooKeeper JMX enabled by default
Using config: /usr/local/zookeeper/apache-zookeeper/bin/../conf/zoo.cfg
Starting zookeeper ... STARTED

# 查看狀態
$ ./zkServer.sh status 
ZooKeeper JMX enabled by default
Using config: /usr/local/zookeeper/apache-zookeeper/bin/../conf/zoo.cfg
Mode: standalone
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看到命令行輸出運行成功，表明運行成功